1. Field
Exemplary embodiments of the present invention relate to an analog-to-digital conversion circuit, an image sensing device having the same, and a method for driving the image sensing device.
2. Description of the Related Art
In general, a charge coupled device (CCD) and a CMOS image sensor (CIS) are widely in use as image pickup devices for converting an optical image into an electrical signal.
Manufacturing a CMOS image sensor through a general CMOS process may be considered more economical than manufacturing an image pickup device using a CCD, as a CMOS image sensor as an analog to digital converting device may be integrated in a single chip. In addition, a CMOS image sensor may be more suitable for low voltage and low power consumption design needed in various mobile applications such as the mobile phones, digital cameras, etc.
A CMOS image sensor may require a high resolution analog to digital converting device for converting an analog signal outputted from an active pixel sensor (APS), which reactives to light, into a digital signal.